Service Manual
1 Service (continued)
General Operation
How the boiler operates | Access modes |
The SYNC uses two (2) advanced stainless steel heat exchangers and two (2) electronic control modules that allow fully condensing operation. The blowers pull in gas and air and push flue products out of the boiler through the heat exchangers and flue piping. The control modules regulate blower speeds to control total boiler firing rate. The gas valves sense the amount of air flowing into the boiler and allow only the right amount of gas to flow.
How the control module operates
The SYNC control modules receive input from boiler sensors. The control modules activate and control the blower and gas valves to regulate heat input and switches boiler, Hot Water Generation (HW) and system pumps on and off as needed. The user/installer programs the control module to meet system needs by adjusting control parameters. These parameters set operating temperatures and boiler operating modes.
Sequence of operation
Table 1A shows control module normal sequences of operation for space heating and HW operation for each individual control module. Additionally, the control modules are programmed to synchronize their combined modulation rates in order to maximize total boiler efficiency. The combined operation sequence is for a typical application, programmed to provide HW priority.
User
The user can view all of the settings on the LCD screen. By entering the user password (0704), the user can adjust the User Set Point, Outdoor Shutdown, Night Setback, Boost, HW Boiler Output Set Point, Backlight Time, and Backlight Brightness settings.
Installer
Most parameters are available only to the installer, accessible only by entering the installer access code (5309).
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